A PIN transaction is a purchase where you enter your four-digit PIN, such as when you choose "debit" at the grocery store checkout terminal or gas pump.

A signature transaction is any purchase where you don't enter your PIN. This includes choosing "credit" at the checkout terminal, paying the check at a restaurant, or making a small purchase that does not require a signature.

When you withdraw money from an ATM, you can potentially be charged two fees: one by the owner of the card, and one by the owner of the ATM. But thankfully, there are ways to avoid those fees.

Many prepaid and traditional debit cards have a network of ATMs that you can withdraw from without incurring a fee from the ATM owner. These are called in-network withdrawals, and they mean you only pay the card withdrawal fee (if there is one).

But if you withdraw from an ATM that your card isn't associated with (out-of-network), you have to pay an ATM surcharge ($2.60 on average) on top of any card fees, unless your card reimburses out-of-network ATM fees.

You overdraw on your account when you spend more than your balance. For example, if you have just $1 in your account but you pay for a $2 coffee, the bank can decide to approve your transaction and charge you an overdraft fee.

Remember, though, that you have to opt in to overdraft protection. You can always opt out of overdraft protection if you do not wish to incur large fees everytime you overdraw your account.

You typically can't deposit a personal check straight into your prepaid debit card – you have to pay someone to cash the check, then buy a cash reload pack and use that to load your card. By the time you're done, you've paid a check cashing fee and a retail reload fee.

Most checking accounts, on the other hand, let you cash or deposit your checks for free.

Some prepaid debit cards let you add a card to your account (for your kids, your spouse, your babysitter...). Some give you the extra card for free, others charge a one-time card fee, and still others charge you an ongoing monthly fee. Many checking accounts don't have this option, which is why you may see the traditional checking account choices disappear from your results.

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